75379981 has 2 divisors, whose sum is σ = 75379982. Its totient is φ = 75379980.

The previous prime is 75379979. The next prime is 75379999. The reversal of 75379981 is 18997357.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61763881 + 13616100 = 7859^2 + 3690^2 .

It is a cyclic number.

It is not a de Polignac number, because 75379981 - 2¹ = 75379979 is a prime.

It is a super-2 number, since 2×75379981² = 11364283071120722, which contains 22 as substring.

Together with 75379979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75379481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37689990 + 37689991.

It is an arithmetic number, because the mean of its divisors is an integer number (37689991).

Almost surely, 2^75379981 is an apocalyptic number.

It is an amenable number.

75379981 is a deficient number, since it is larger than the sum of its proper divisors (1).

75379981 is an equidigital number, since it uses as much as digits as its factorization.

75379981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 476280, while the sum is 49.

The square root of 75379981 is about 8682.1645342622. The cubic root of 75379981 is about 422.4273296813.

The spelling of 75379981 in words is "seventy-five million, three hundred seventy-nine thousand, nine hundred eighty-one".